The present invention relates to the field of golf equipment.
Golf is a game in which one or more clubs are used to hit a ball into a series of cups. A club typically comprises a handle and a head connected by a shaft, the club being swung so that the face of the head strikes the ball. The alignment of the head at the point of impact with the ball is critical in that it largely determines the direction of motion of the ball. Part of the skill of golfing is the ability to align the club in the proper alignment, neither "toe-in" which hooks the ball, nor "toe-out" which slices the ball. The terms "hook" and "slice" are used in the sense normally attributed to them by golfers. A "hook" describes a mid-flight veering of the ball to the side of the dominant hand, while a "slice" describes a mid-flight veering of the ball to the side of the non-dominant hand. Learning to swing the club in the proper alignment is difficult for many individuals. The difficulty may be especially great when using a club such as a driver which has a relatively long shaft and a relatively heavy head.
One solution is to practice swinging at a relatively large number of balls at a driving range. This solution provides rapid feedback on each swing, and the golfer can attempt to adjust his swing accordingly. There are, however, significant drawbacks. A driving range may be expensive, inconveniently located, crowded, intemperate or even closed at the time the golfer wishes to use it. Further, the feedback to the golfer regarding the nature of his swing is delayed by several seconds. A golfer often cannot tell whether he has hooked, sliced or hit the ball square until after the swing is over and the ball is well down range. The word "square" as used in this application is defined as the proper horizontal alignment of the face of a club head with respect to a ball, i.e. neither toe-in nor toe-out. Any alignment other than a square alignment is considered to be non-square.
Another solution is for a golfer to practice his swing in front of an instructor, or in front of a video camera. In both instances the golfer can improve his swing over time, but the speed of improvement is hampered by the delay in feedback.